1. Field of the Invention
The present invention relates to an encoder module, and more particularly, to an encoder module adapted to be used in a three-dimensional cursor control device.
2. Description of the Prior Art
Cursor control device is one of commonly used computer peripherials under Windows based operation system. Cursor control devices with different structures have been provided in the market, e.g. computer mice, trackballs, touch pads, digitizers and joysticks, depending on different types of the Windows based operation system, to comply with needs of various software applications' cursor control. And obviously, the structures of different cursor control devices for generating cursor control signals will differ from each other.
Taking computer mouse for example, the most well-known computer mouse is a two-dimensional type. Its operation theory for cursor control is rotate two sets of encoder wheels by frictioning a ball to intermittently mask the light emitted by a pair of light sources to generate the effect of close/open of lights. Voltage signals are generated after the lights penetrates through the encoder wheels and are respectively received by a pair of photodetectors. Signals for controlling cursor movements are generated by processing the voltage signals.
Two-dimensional computer mice are not applicable in some way due to the gradual increase of software applications. Therefore, three- or even more dimensional computer mice are invented and produced in the market. Consequently, how to simply and make more convenient the manipulation of the cursor control signal generating mechanism for three-dimensional computer mice will thus become the major subject.